# Puzzle No. 509: Triomino Sudoku [Daily League]

I’ve got wayyy too much to do these days, so I’ve pretty much stopped any regularity on this blog. I might make the rare post though, like this one. I was a little bored of work and had some time so quickly explored this variant that’s part of the Indian Sudoku Championship which will be held online on LMI in about 13.5 hours. This one is pretty difficult (as are all variants I randomly and quickly post here when bored), but has some nice steps to get started.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay (though I’m not yet sure if this one can be supported there, but take a leap of faith, maybe it will be!).

Rules – Place a digit from 1 to 6 into each empty cell or blacken the cell so that each digit appears exactly once in every row, column, and outlined 3×3 region along with three black(shaded) cells. Each black(shaded) cell should be part of an orthogonally connected group of three blackened(shaded) cells (a triomino). No two triominoes can share an edge.

Enjoy!

P509

# Puzzle No. 500 – 9 Shady Masterminds [Special] [Marathon]

I thought quite a bit about what I wanted for my 500th puzzle here. There was a stage when I thought I’d just ignore the milestone and post something normal. Then I got a bit of an idea of a simple theme which might still give out a nice solve path with different logical deductions combining.

The puzzle that resulted from this idea is pretty narrow and quite difficult, according to my and Swaroop‘s test solving experiences. Still, I think its ended up being quite varied in the thinking required and I like how it turned out.

Unlike my usual approach of posting a single image, for this puzzle I am attaching a PDF instead. This PDF has 4 pages. The first page contains the puzzle. The 2nd and 3rd pages contain the rules (The length is just because there are 9 different puzzles to cover, but most of them are familiar and should just be a quick read-through). There are two newer puzzle types, and one variant which I couldn’t immediately find an example for, so I have added 6×6 examples for these three rule-sets. The remaining are all classics, so I’ve just linked to the respective page where I got the rules from, and you can visit these links if you want an example. If you are new here and haven’t seen those sites before, I suggest visiting them anyway for more great puzzles.

Here’s the PDF:

Please let me know in the comments or by mail (prasanna16391@gmail.com) if you have any queries regarding the rules or any other issues.

# Puzzle no. 489 : Thermo Sudoku [Daily League]

Check this post for reference on this blog’s 3 main types of posts from now on.

First, PDFs!

The League of Extraordinary Ladies and Gentleman_week04_2014

The League of Extraordinary Ladies and Gentleman_week05_2014

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.

This is also Ex-Championship but, I changed it a little to make it easier for the Championship. This is the original hard version. There’s a few challenging spots.

Rules – Follow regular Sudoku rules. Additionally, some thermometer shapes are in the grid; digits must be strictly increasing from the round bulb to the flat end.

Rated – Hard.

Enjoy!

P489

# Puzzle No. 484-487 : Polish Qualifier Puzzles [Ex-Contest]

Check this post for reference on this blog’s 3 main types of posts from now on. I’ll post smaller sets like this one here, and keep I’m hoping to start a patronage system of my own for bigger sets. More on that later.

Right, just about got this in today. I won’t be home over the weekend, so whether I get a sample of the Instructive tagged post out depends on getting an internet connection where I’ll be staying. I’ll be back on Monday though, so will have it up at latest by Monday night.

This set might seem to have some tough puzzles for a National qualifier (not finals), but I was told that there were many easy puzzles already. Two of the puzzles are types I saw in a book purchased from team Japan at the WPC. It is a collaborative work featuring Serkan Yurekli and many Japanese authors. I’ve changed one rule slightly for Heyawacky block (more an omission than a change) but I prefer it this way personally. Anyway, here they are. Enjoy!

Rules –

484 – Yajilin.

485 – Heyawacky Block – Blacken some cells so that all remaining cells must be connected orthogonally. Any single horizontal or vertical line of white cells cannot traverse more than one thick line. Numbers indicate the amount of black cells in that region. If there is no number, there can be 0 or more black cells. Inside each region, all black cells are connected orthogonally. But black cells must not be orthogonally connected beyond the border lines.

486 – Nurikabe.

487 – Snake BY – Draw in the grid a snake, not touching itself, even diagonally. Each outlined region must contain exactly 3 cells occupied by the snake. The regions that contain the head and the tail of the snake are marked by grey color.

P484

P485

P486

P487

# Puzzle No. 478 : Christmas Loop

Just about got a crazy idea in time to execute it on Christmas day. Thanks to Chaotic Iak and Tiit Vunk for testing this one. The puzzle itself is pretty difficult. The rules are complex. So, Merry Christmas everyone! *evil laugh*

Oh and thanks to Tawan for hosting the wonderful contest Colour Restore, which I won, because I’m the KING of Rock-Paper-Scissors B-) Actually, that’s where the entire inspiration for this idea started, the colours, which is mainly why I wanted the colours to be able to help in the solve in some way. So thanks for that too.

Rules –

Part 1 – Cipher Fillomino – Using Fillomino rules, divide the grid into regions. The numbers are all replaced by colours. Same numbers are represented by the same colour, and different numbers by a different colour.

Part 2 – Regional Railroads – Draw a loop that passes through every cell of the grid and doesn’t overlap itself. It can cross only on cells with a + sign and has to cross on every cell with a + sign. Each region in the grid must have at least one continuous instance of the loop passing through all it’s cells.

Part 3 (Not necessary for the puzzle to be unique. You can skip ahead to the puzzle with the rules above without this helper) Colour Combinations – The 3 common ways that colours mix to form other colours ((Red, Blue, Purple)(Blue, Yellow, Green)(Red, Yellow, Orange)) will form 3 groups where the colour values can make the arithmetic equation A+B=C valid somehow. (e.g. Red +Purple = Blue)

Rated – Hard of course.

If you want an easier version than even the part 3 helper, here’s an image with the equations between colours directly given.

P478

# Puzzle No. 475 : Untouch – AntiKnight Sudoku [Daily League]

First, PDF!

The League of Extraordinary Ladies and Gentleman_week48

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.

I’m gonna need a while to get used to the Thursday schedule. Totally forgot that this is my day now. This one’s quickly made, and so some will feel this is “half” the puzzle it could be. It’s still challenging though, and should still be fun I hope.

Rules – Follow regular Sudoku rules. Additionally, same numbers cannot touch diagonally and also can’t be a chess knight’s step away from each other.

Rated – Hard.

Enjoy!

P475

# Puzzle No. 471 : Weighted Frame Sudoku [Daily League]

First, PDF!

The League of Extraordinary Ladies and Gentleman_week47

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.

This puzzle’s really tough, I think. The Weighted rules do play in nicely for the break-in.

Rules – Follow regular Sudoku rules. Additionally, a clue outside gives the sum of the first 3 numbers in that direction. Also, the numbers in shaded cells will count for double their values for any sum they are part of.

Rated – Hard.

Enjoy!

P471

# Puzzle No. 469, 470 : Regional Tapa, Regional Snake

I took a week long break from puzzle construction, which was a little “forced”. Now I’m starting again from tomorrow,  and I want to start fresh, so discarding all my “reserve” puzzles and starting new on everything, as I like to do after a break.

The Regional Tapa isn’t that difficult but the Snake is.

Rules –

P469 – Rules of Tapa. Additionally, a clue also indicates the length of shaded cell groups in its region (in the exact configuration as the clue). Some regions may not have clues and have no restrictions. A “?” can stand for any number, but the number(s) needs to be constant for the clue cell as well as the region it is in.

P470 – Find a snake in the grid whose body consists of horizontal and vertical segments. The snake’s body never touches itself, not even diagonally. The head and tail of the snake are not given. Numbers in each of the regions surrounded by thick lines denote the number of cells occupied by the snake in that region.

Enjoy!

P469

P470

# Puzzle No. 468 : Skyscraper Sudoku [Daily League]

First, a note about PDFs of previous weeks. Christoph Seeliger of Germany has kindly taken up PDF responsibilities with slight changes to how Tom used to do it. I’ll start linking to the PDFs from week 47 onwards, but 37-46 are all on our Facebook group.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay.

I realize I posted a Skyscraper variant just 2 weeks ago, but this is mainly a “reject” from a set I provided. It is rejected for being too hard, or to be more accurate, requiring too much non-Sudoku logic. I agree with this assessment, and still think its a nice Sudoku to solve. So here. (Yeah, I’ve gotten into the habit of saying “so here” now)

Rules for SudokuAdditionally, each number in the grid represents the height of the skyscraper in each cell. The digits outside the grid indicate the number of skyscrapers seen from the corresponding direction.

Rated – Hard.

Enjoy!

P468

# Puzzle No. 456 : Sudoku +/-4 [Daily League]

More of the practice puzzles I wrote for Team India. This variation was in the WPC and IS pretty puzzly, but I’m pressed for time and this solved the purpose of a Sudoku post.

Remember that you can solve the puzzles from the League online on the Sudokucup Guest League page with a 24h delay. However, I spoke to Karel and chances are this one might not be interface friendly. Do check in tomorrow if you want to though, just in case.

Rules –

Enter whole numbers between -4 and +4, inclusive, into the grid so that each row, column and region contains all possible numbers exactly once. Clues outside the grid indicate the sum of all numbers that appear between the clue and the cell containing zero in that row/column. Some cells already contain a number. However, the signs for these clues are not indicated, it is part of the puzzle to determine whether they are positive or negative values.

Rated – Hard.

Enjoy!

P456